Vertically collapsible upright for lifting gantries and the like

ABSTRACT

For a vertically collapsible apparatus including an upper beam, such as lifting gantries, scaffoldings, . . . , a vertical upright or leg, normally used in pair, said leg comprising three elements pivoting on one another and on the beam by four axes of articulation (as known per se), wherein the four axes are parallel and perpendicular to the axis of the beam. The three elements are: a triangular element articulated by its apex on the beam at a distance of the end thereof, a trapezoidal element pivoting at the base of the first triangular element, and another triangular element having its apex articulated on the end of the beam and its base articulated on the trapezoidal element between the large and the small base thereof, whereby said apparatus can assume an operating and a transport position by a simple and practical manual operation.

United States Patent Durand et al.

VERTICALLY COLLAPSIBLE UPRIGHT FOR LIFTING GANTRIES AND THE LIKE Inventors: Pierre E. Durand, 39 rue des Noirets, 21 Gevrey-Chambertin; Jean Ch. Durand, 56 rue du Transvaal, 21 Dijon, both of France Filed: June 6, 1972 Appl. No.: 260,218

US. Cl. .L 182/155, 182/141 Int. Cl F16m 11/00 Field of Search 182/155, 153, 181-185,

1s2/225,'152, 141; 248/166, 439; 211/178; 135/1 A, 4A

References Cited UNITED STATES PATENTS 7/1934 Johnson 182/155 5/1956 Sheard 182/152 4/1963 McDonough 182/63 3,235,038 2/1966 Nesslinger... 248/166 3,351,078 ll/l967 Kleiman 135/] A 3,628,765 12/1971 Sanders 182/155 Primary Examiner-Reinaldo P. Machado Attorney-Otto John Munz '57 ABSTRACT For a vertically collapsible apparatus including an upper beam, such as lifting gantries, scaffoldings, a vertical upright or leg, normally used in pair, said leg comprising three elements pivoting on one another and on the beam by four axes of articulation (as known per se), wherein the four axes are parallel and perpendicular to the axis of the beam. The three elements are a triangular element articulated by its apex on the beam at a distance of the end thereof, a trapezoidal element pivoting at the base of the first triangular element, and another triangular element having its apex articulated on the end of the beam and its base articulated on the trapezoidal element between the large and the small base thereof, whereby said apparatus can assume an operating and a transport position by a simple and practical manual operation.

6 Claims, 5 Drawing Figures miminmzs nan 3.741.338

sum-1 0r 2 PATENTED JUN26 I975 sum 2 OF 2 VERTICALLY COLLAPSIBLE UPRIGHT FOR LIFTING GANTRIES AND THE LIKE BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comes within the field of vertically collapsible apparatus and relates in particular to lifting gantries, scaffoldings, etc.; it is concerned more particularly with articulated legs enabling apparatus of this type, equipped therewith, to give normal performance and to be folded for transport purposes, thus considerably reducing their over-all height above the ground without increasing any of their other dimensions.

The main result, where such apparatus is concerned, is that it can be moved about without difficulty and towed on roads.

2. Description of the Prior Art The movement and the transport of lifting gear have always raised problems essentially connected with the generally considerable dimensions of such equipment, the dimensions being necessitated by the work which has to be carried outat a height and in all directions and for which the apparatus is designed. In order to solve these problems, systems are known in which certain components of the lifting gear are folded one upon the other, as in the case of the jib of a crane folded back on the stock. I

Devices are also known in which one or more components are collapsible, each one in itself, and also on one another, after dismantling this solution has been adopted for gantries designed for certain special purposes and only having to bear a comparatively moderate load.

There is also apparatus in which the dimensions are reduced by the telescopic assembly of certain elements, variations in the space occupied sometimes being obtained by adding or removing parts of one or more elements. At all events, the manipulations involved in changes of gauge are difficult, sometimes extremely so, necessitating additional measures which are not adaptable to the type of gantry of which the use is tending to become general on building sites.

SUMMARY OF THE INVENTION The purpose of the invention is to enable a lifting gantry to be reduced in size to the maximum possible extent, by a simple and practical manual operation, in order to cause it to assume the transport position, after which the said gantry can be caused to assume the operating position, by a further simple and practical manual operation.

A gantry according to the invention comprises an upper beam and two vertical uprights of generally triangular shape, such as those already known per se. It is characterized by the fact that each upright comprises three elements, i.e.

a first element, of a generally triangular shape, of which the apex is articulated at a certain distance from one end of the beam, and a base a second element, of generally trapezoidal shape, with a small base articulated to the base of the first element and a large base preferably fitted with wheels a third element, of a generally triangular shape, having an apex articulated to the end of the beam and a base articulated to the second element.

In profile the three elements form an articulated quadrilateral figure which becomes a triangle when in the extended position the first element and the second element are situated in one and the same plane, which is' then vertical.

Briefly, it may be said that the vertical uprights are triangles of which each side is in two parts, articulated to each other, enabling the lower and the upper part of the triangle to be folded over onto each other. The upper part is articulated to the beam and the lower part connected to the latter by stiffening devices at their two ends, i.e. to the lower part and to the beam respectively.

Means are also provided for moving each upright from the operating position (in which the upper and lower parts are vertical and in line) to the collapsed position (in which the upper and lower parts are folded towards each other) and vice versa.

BRIEF DESCRIPTION OF THE DRAWINGS DESCRIPTION OF THEYPREFERRED EMBODIMENT Referring first to FIGS. 3 and 5, a lifting gantry, marked as a whole, essentially consists of a beam 2 supported by two uprights 1 of a generally triangular shape, this arrangement being already known per se. It

is then in the operating position.

The invention enables the gantry 100 to be moved from the position shown in FIG. 3 to that shown in FIG. 4, known as the collapsed position.

For this purpose each upright l is not rigid but consists of two elements 11 and 12, articulated to each other in 'a manner which will be described with reference to FIGS. 1 and 2. These diagrams show the righthand upright and part of the beam 2 the upright 1 consists of two parts, one part 11 of a generally triangular shape and the other part 12 of a generally trapezoidal shape.

The triangular part 11 consists of two steel tubes 1 11 and 112, rigidified by a tube 113 welded to the tubes 111 and 112 these latter converge towards a strap 3,

of steel plate, to the sole of which they are welded. The

strap 3 has a boring 144 (FIG. 2) in each of its two vertical cheeks, these two borings having one and the same horizontal axis.

The beam 2 bears a strap 10 of which the vertical cheeks fit into those of the strap 3. The vertical cheeks of the straps 3 and 10 are traversed from side to side by one and the same horizontal shaft 14, which constitutes the main articulation shaft of the supporting upright 1 on the beam 2.

At the upper end of the part 11 the tubes 111 and 112 bear fiat bars 114 and 115 respectively.

The trapezoidal part 12 Consists of tubes 121 and 122, rigidified at the bottom by a tube 126 and at their point of convergence by a tube 123. The tubes 123 and a bear flat bars 127 127 and 114, on the onehand, and 128and 115, on the other, being opposite to one another,-borings pass through the tubes 111 and 121 and the flat bars 114 and 127 on the one hand and through'the tubes 112 and 122 and the flat bars 128 and 115 on theother these borings are coaxial and each traversed by a shaft 41 on the one hand and 51 on the: other, the shafts being supported and locked in position in the manner already known. Furthermore, borings 42 and 52, parallel to the first borings mentioned and situated lower down, enable the parts 11 and 12 to be rendered inte- 20 i to the tube 123. The sector gral with each other in the operating position by means of suitable pins.

The assembly consisting of tube 121, the flatbar l27,

hard? device. engages a bracket37 welded, tofthe tube 121. At the outlet from the pull hard" device the cable: 31 passes over a; reversing pulley 45 rotating on the shaft of thestrap46 welded to the. tube 121.

The pull hard apparatus 33 of each of the two sup- N porting uprights and gantryis situated on the same side of thislatter, sothatsinc lateral access is provided from one and thesa meside the system can. be con trolled manually byanoperator in this position, who

. will not be hindered by the movements of the parts of Y which the gantry consists, access from the other side of the latter not being required by him. This arrangement is illustrated by the diagrams of the pull hard devices. 3-3inFIGS. 3 and 5. The tackle 32 engages the shaft 8 of the strap 9.,by a closed hook at one end and by a, cable 39 at the other end, attached to a sector 40 comprising a securing strap 43 (FIG. 1) and a guide groove.

flat bar 114, tube 111 and shaft 41 forms a knuckle joint marked 4. Similarly, the assembly consisting of tube 122, flat bar 128, flat bar 115, tube 112 and shaft 51 constitutes a knuckle joint marked 5.

5 used), can be Two stiffening tubes 6 and 7 for the gantry 100 are I articulated, on the one hand, by a shaft 8 'to a strap 9 f welded to the beam 2, the said tubes 6 and 7being articulated by a shaft61 to the tube 121 and by a shaft 62 to the tube 122 respectively.

Rubber stops such as and 16 (FIG. 1) are affixed 44 (FIG. 2) of the cable 39. The sector 40 is welded to the tube 123. This securing system is consolidatedby welded to the sector 40 and 40 is thus integral with the" tubes 124and 125 (FIG. 1)

trapezoidal part 12, and it can be easily understood that by operating the tackle. 32 the said over it.

The operationof openingout or collapsing the gantry is as follows: the gantrybeing in the collapsed position to lugs 15a and 16a welded at right angles to the flat bars 115 and 128 and also to the flat bars 114 and 127,

in order to provide the necessary elasticity at the beginning of the collapsing movement.

To the lower end of the two tubes 1'21 and 122 are welded a strap 17 forthe tube 121 and a strap 18 for the tube 122 each of these straps bears a roller, such as 19 and 20, rotating on shafts 21 and 22 respectively. The rollers 19 and are the normal means of supporting the gantry on the ground in its operating position. I

The use of rollers as a support is suitable for sufficiently hard and level ground, taking into account the loading of the gantry; in the case of excessively soft or uneven ground the supporting surface has to be increased or the level evened out, or both together, this being the object achieved by means of the devices 23 and24 which are adjustable in height and each of which consists of a screw 25 passing through the tube 126 and engaging two nuts 26 and 27, the screw 25 being provided at the top with a cylindrical head 28 having a boring 29, to enable it to be operated with a tommy bar; the said screw 25 is provided at the bottom with a steel plate 30 of suitable area, which can be increased by affixing a further suitable surface, as far as the level of the supporting ground. The device 23 is identically similar to the device 24 just described and also symmetrical thereto.

(FIG. 2 or 4),the operator uses the lever 34 (FIG. 2)

of the pull hard device33 (FIG. 2) to exert a tractive force via the cable 31and the tackle 32 (arrow A in FIG. 2) on the cable 39, causing the sector 40 (FIG. 2) to rotate in the direction shown by the'arrow A. The sector 40, integral with the tube 123 and with the whole of the part 12, sets the said part 12 in rotation this part 12 can then only rise, by bearing on the ground via the rollers 19 and 20, likewise raising the part 11 of the upright and the beam 2, via the knuckle joints 4 and 5 the acute angle increase between the parts 11 and 12 of the upright, thus aligning the tubes 111 and 121 (FIG. 1) as well as tubes 112 and 122. The supporting upright l is then extended and vertical, the cable 39 being stretched and completely outside the groove 44 (FIG. 2) of the sector 40.

By the choice of their articulations the stiffening tubes 6 and 7 enable the gantry to be rendered longitudinally stable, not only in the operating position but also duringall manipulations, which is indispensable.

The operation of colappsing the gantry is carried out by acting on the pullhard device 33 in the direction required to slacken the cable 31 the sector 40 then rotates in the opposite direction to that mentioned above the effect of this mainpulation, however, as soon asit has been commenced, via the elastic stops 15 and 16,

is to control the movement and not to initiate it, as in r hardly one third of its height in the operation position when so collapsed it may by placed without difficulty on a suitable towing vehicle, which enables it to be moved about a site by hand, as required, or towed at trapezoidal part 12 other, for obvious reasons of advantageous speeds from one side to another, despite the limits of the gauges of the public highway, and a further object in view is very satisfactorily achieved by the flexibity of use.

The scope of the invention must not be regarded as being limited to the specific cases or to the constructional example described in the present memorandum but only as being limited'by the claims which now follow.

We claim:

1. Articulated leg, normally used by pair and adapted to raise or lower a rigid upper beam between an operating position and a folded position, the leg comprising three elements articulated to one another, at least one of these three elements being articulated to the said upper rigid element, wherein the improvements comprise the combination of a high element of generally triangular shape of which the apex is articulated according to a first axis perpendicularto that of the upper beam and at a distance from one of its ends, and a base a lower element of generally trapezoidal shape, having a small base articulated to the base of the said high element, according to a second axis parallel to said first axis, and a large base serving as a support for the legs a stabilizing element of generally triangular shape, having an apex articulated to the end of the upper beam, according to a third axis parallel to said first axis and a base articulated to the low element according to a fourth axis parallel to said second axis andat a distance thereof.

2. Articulated leg according to claim 1, wherein means are provided for moving the said articulated leg from the folded position to the operating position, the said means consisting of a grooved sector integral with the low element and a traction cable passing round and fixed to the said grooved sector at one end and attached to a point on the upper beam on the other end.

3. Articulated leg according to claim 2, wherein the said grooved sector is made integral with the low element by means of a tubular element operating under torsion.

4. Articulated leg according to claim 3, wherein the said high element, low element and stabilizing element, when in the folded position, form two articulated quadrilate ral figures in planes converging towards the upper beam, while in their operating position they form two triangles, the plane of the triangle of the stabilizing element intersecting, by the base of the said triangle, the single plane then formed by the high element and the low element, this intersection taking place below the articulation of the said high and low elements.

5. Articulated leg according to claim 4, wherein the low element is articulated to the high element by means of two knuckle joints.

6. Articulated leg according to claim 5, wherein the said two knuckle joints are completed by a pair of elastic stops coming in contact with each other in the operating position,- which enables the apparatus to be moved to the folded position by reducing the trac tive stress prevailing between the cable looped over the grooved sector integral with the low element.

' :r' in 

1. Articulated leg, normally used by pair and adapted to raise or lower a rigid upper beam between an operating position and a folded position, the leg comprising three elements articulated to one another, at least one of these three elements being articulated to the said upper rigid element, wherein the improvements comprise the combination of : a high element of generally triangular shape of which the apex is articulated according to a first axis perpendicular to that of the upper beam and at a distance from one of its ends, and a base ; a lower element of generally trapezoidal shape, having a small base articulated to the base of the said high element, according to a second axis parallel to said first axis, and a large base serving as a support for the legs ; a stabilizing element of generally triangular shape, having an apex articulated to the end of the upper beam, according to a third axis parallel to said first axis and a base articulated to the low element according to a fourth axis parallel to said second axis and at a distance thereof.
 2. Articulated leg according to claim 1, wherein means are provided for moving the said articulated leg from the folded position to the operating position, the said means consisting of a grooved sector integral with the low element and a traction cable passing round and fixed to the said grooved sector at one end and attached to a point on the upper beam on the other end.
 3. Articulated leg according to claim 2, wherein the said grooved sector is made integral with the low element by means of a tubular element operating under torsion.
 4. Articulated leg according to claim 3, wherein the said high element, low element and stabilizing element, when in the folded position, form two articulated quadrilateral figures in planes converging towards the upper beam, while in their operating position they form two triangles, the plane of the triangle of the stabilizing element intersecting, by the base of the said triangle, the single plane then formed by the high element and the low element, this intersection taking place below the articulation of the said high and low elements.
 5. Articulated leg according to claim 4, wherein the low element is articulated to the high element by means of two knuckle joints.
 6. Articulated leg according to claim 5, wherein the said two knuckle joints are completed by a pair of elastic stops coming in contact with each other in the operating position, which enables the apparatus to be moved from the folded position by reducing the tractive stress prevailing between the cable looped over the grooved sector integral with the low element. 